1 files changed, 201 insertions, 158 deletions

diff --git a/fs/nilfs2/recovery.c b/fs/nilfs2/recovery.c
index bae2a516b4ee..d0c35ef39f6a 100644
--- a/fs/nilfs2/recovery.c
+++ b/fs/nilfs2/recovery.c
@@ -91,27 +91,9 @@ static int nilfs_warn_segment_error(int err)
         return -EINVAL;
 }
 
-static void store_segsum_info(struct nilfs_segsum_info *ssi,
-                              struct nilfs_segment_summary *sum,
-                              unsigned int blocksize)
-{
-        ssi->flags = le16_to_cpu(sum->ss_flags);
-        ssi->seg_seq = le64_to_cpu(sum->ss_seq);
-        ssi->ctime = le64_to_cpu(sum->ss_create);
-        ssi->next = le64_to_cpu(sum->ss_next);
-        ssi->nblocks = le32_to_cpu(sum->ss_nblocks);
-        ssi->nfinfo = le32_to_cpu(sum->ss_nfinfo);
-        ssi->sumbytes = le32_to_cpu(sum->ss_sumbytes);
-
-        ssi->nsumblk = DIV_ROUND_UP(ssi->sumbytes, blocksize);
-        ssi->nfileblk = ssi->nblocks - ssi->nsumblk - !!NILFS_SEG_HAS_SR(ssi);
-
-        /* need to verify ->ss_bytes field if read ->ss_cno */
-}
-
 /**
- * calc_crc_cont - check CRC of blocks continuously
- * @sbi: nilfs_sb_info
+ * nilfs_compute_checksum - compute checksum of blocks continuously
+ * @nilfs: nilfs object
  * @bhs: buffer head of start block
  * @sum: place to store result
  * @offset: offset bytes in the first block
@@ -119,23 +101,25 @@ static void store_segsum_info(struct nilfs_segsum_info *ssi,
  * @start: DBN of start block
  * @nblock: number of blocks to be checked
  */
-static int calc_crc_cont(struct nilfs_sb_info *sbi, struct buffer_head *bhs,
-                         u32 *sum, unsigned long offset, u64 check_bytes,
-                         sector_t start, unsigned long nblock)
+static int nilfs_compute_checksum(struct the_nilfs *nilfs,
+                                  struct buffer_head *bhs, u32 *sum,
+                                  unsigned long offset, u64 check_bytes,
+                                  sector_t start, unsigned long nblock)
 {
-        unsigned long blocksize = sbi->s_super->s_blocksize;
+        unsigned int blocksize = nilfs->ns_blocksize;
         unsigned long size;
         u32 crc;
 
         BUG_ON(offset >= blocksize);
         check_bytes -= offset;
         size = min_t(u64, check_bytes, blocksize - offset);
-        crc = crc32_le(sbi->s_nilfs->ns_crc_seed,
+        crc = crc32_le(nilfs->ns_crc_seed,
                        (unsigned char *)bhs->b_data + offset, size);
         if (--nblock > 0) {
                 do {
-                        struct buffer_head *bh
-                                = sb_bread(sbi->s_super, ++start);
+                        struct buffer_head *bh;
+
+                        bh = __bread(nilfs->ns_bdev, ++start, blocksize);
                         if (!bh)
                                 return -EIO;
                         check_bytes -= size;
@@ -150,12 +134,12 @@ static int calc_crc_cont(struct nilfs_sb_info *sbi, struct buffer_head *bhs,
 
 /**
  * nilfs_read_super_root_block - read super root block
- * @sb: super_block
+ * @nilfs: nilfs object
  * @sr_block: disk block number of the super root block
  * @pbh: address of a buffer_head pointer to return super root buffer
  * @check: CRC check flag
  */
-int nilfs_read_super_root_block(struct super_block *sb, sector_t sr_block,
+int nilfs_read_super_root_block(struct the_nilfs *nilfs, sector_t sr_block,
                                 struct buffer_head **pbh, int check)
 {
         struct buffer_head *bh_sr;
@@ -164,7 +148,7 @@ int nilfs_read_super_root_block(struct super_block *sb, sector_t sr_block,
         int ret;
 
         *pbh = NULL;
-        bh_sr = sb_bread(sb, sr_block);
+        bh_sr = __bread(nilfs->ns_bdev, sr_block, nilfs->ns_blocksize);
         if (unlikely(!bh_sr)) {
                 ret = NILFS_SEG_FAIL_IO;
                 goto failed;
@@ -174,12 +158,13 @@ int nilfs_read_super_root_block(struct super_block *sb, sector_t sr_block,
         if (check) {
                 unsigned bytes = le16_to_cpu(sr->sr_bytes);
 
-                if (bytes == 0 || bytes > sb->s_blocksize) {
+                if (bytes == 0 || bytes > nilfs->ns_blocksize) {
                         ret = NILFS_SEG_FAIL_CHECKSUM_SUPER_ROOT;
                         goto failed_bh;
                 }
-                if (calc_crc_cont(NILFS_SB(sb), bh_sr, &crc,
-                                  sizeof(sr->sr_sum), bytes, sr_block, 1)) {
+                if (nilfs_compute_checksum(
+                            nilfs, bh_sr, &crc, sizeof(sr->sr_sum), bytes,
+                            sr_block, 1)) {
                         ret = NILFS_SEG_FAIL_IO;
                         goto failed_bh;
                 }
@@ -199,64 +184,76 @@ int nilfs_read_super_root_block(struct super_block *sb, sector_t sr_block,
 }
 
 /**
- * load_segment_summary - read segment summary of the specified partial segment
- * @sbi: nilfs_sb_info
- * @pseg_start: start disk block number of partial segment
- * @seg_seq: sequence number requested
- * @ssi: pointer to nilfs_segsum_info struct to store information
+ * nilfs_read_log_header - read summary header of the specified log
+ * @nilfs: nilfs object
+ * @start_blocknr: start block number of the log
+ * @sum: pointer to return segment summary structure
  */
-static int
-load_segment_summary(struct nilfs_sb_info *sbi, sector_t pseg_start,
-                     u64 seg_seq, struct nilfs_segsum_info *ssi)
+static struct buffer_head *
+nilfs_read_log_header(struct the_nilfs *nilfs, sector_t start_blocknr,
+                      struct nilfs_segment_summary **sum)
 {
         struct buffer_head *bh_sum;
-        struct nilfs_segment_summary *sum;
+
+        bh_sum = __bread(nilfs->ns_bdev, start_blocknr, nilfs->ns_blocksize);
+        if (bh_sum)
+                *sum = (struct nilfs_segment_summary *)bh_sum->b_data;
+        return bh_sum;
+}
+
+/**
+ * nilfs_validate_log - verify consistency of log
+ * @nilfs: nilfs object
+ * @seg_seq: sequence number of segment
+ * @bh_sum: buffer head of summary block
+ * @sum: segment summary struct
+ */
+static int nilfs_validate_log(struct the_nilfs *nilfs, u64 seg_seq,
+                              struct buffer_head *bh_sum,
+                              struct nilfs_segment_summary *sum)
+{
         unsigned long nblock;
         u32 crc;
-        int ret = NILFS_SEG_FAIL_IO;
+        int ret;
 
-        bh_sum = sb_bread(sbi->s_super, pseg_start);
-        if (!bh_sum)
+        ret = NILFS_SEG_FAIL_MAGIC;
+        if (le32_to_cpu(sum->ss_magic) != NILFS_SEGSUM_MAGIC)
                 goto out;
 
-        sum = (struct nilfs_segment_summary *)bh_sum->b_data;
-
-        /* Check consistency of segment summary */
-        if (le32_to_cpu(sum->ss_magic) != NILFS_SEGSUM_MAGIC) {
-                ret = NILFS_SEG_FAIL_MAGIC;
-                goto failed;
-        }
-        store_segsum_info(ssi, sum, sbi->s_super->s_blocksize);
-        if (seg_seq != ssi->seg_seq) {
-                ret = NILFS_SEG_FAIL_SEQ;
-                goto failed;
-        }
+        ret = NILFS_SEG_FAIL_SEQ;
+        if (le64_to_cpu(sum->ss_seq) != seg_seq)
+                goto out;
 
-        nblock = ssi->nblocks;
-        if (unlikely(nblock == 0 ||
-                     nblock > sbi->s_nilfs->ns_blocks_per_segment)) {
+        nblock = le32_to_cpu(sum->ss_nblocks);
+        ret = NILFS_SEG_FAIL_CONSISTENCY;
+        if (unlikely(nblock == 0 || nblock > nilfs->ns_blocks_per_segment))
                 /* This limits the number of blocks read in the CRC check */
-                ret = NILFS_SEG_FAIL_CONSISTENCY;
-                goto failed;
-        }
-        if (calc_crc_cont(sbi, bh_sum, &crc, sizeof(sum->ss_datasum),
-                          ((u64)nblock << sbi->s_super->s_blocksize_bits),
-                          pseg_start, nblock)) {
-                ret = NILFS_SEG_FAIL_IO;
-                goto failed;
-        }
-        if (crc == le32_to_cpu(sum->ss_datasum))
-                ret = 0;
-        else
-                ret = NILFS_SEG_FAIL_CHECKSUM_FULL;
- failed:
-        brelse(bh_sum);
- out:
+                goto out;
+
+        ret = NILFS_SEG_FAIL_IO;
+        if (nilfs_compute_checksum(nilfs, bh_sum, &crc, sizeof(sum->ss_datasum),
+                                   ((u64)nblock << nilfs->ns_blocksize_bits),
+                                   bh_sum->b_blocknr, nblock))
+                goto out;
+
+        ret = NILFS_SEG_FAIL_CHECKSUM_FULL;
+        if (crc != le32_to_cpu(sum->ss_datasum))
+                goto out;
+        ret = 0;
+out:
         return ret;
 }
 
-static void *segsum_get(struct super_block *sb, struct buffer_head **pbh,
-                        unsigned int *offset, unsigned int bytes)
+/**
+ * nilfs_read_summary_info - read an item on summary blocks of a log
+ * @nilfs: nilfs object
+ * @pbh: the current buffer head on summary blocks [in, out]
+ * @offset: the current byte offset on summary blocks [in, out]
+ * @bytes: byte size of the item to be read
+ */
+static void *nilfs_read_summary_info(struct the_nilfs *nilfs,
+                                     struct buffer_head **pbh,
+                                     unsigned int *offset, unsigned int bytes)
 {
         void *ptr;
         sector_t blocknr;
@@ -265,7 +262,8 @@ static void *segsum_get(struct super_block *sb, struct buffer_head **pbh,
         if (bytes > (*pbh)->b_size - *offset) {
                 blocknr = (*pbh)->b_blocknr;
                 brelse(*pbh);
-                *pbh = sb_bread(sb, blocknr + 1);
+                *pbh = __bread(nilfs->ns_bdev, blocknr + 1,
+                               nilfs->ns_blocksize);
                 if (unlikely(!*pbh))
                         return NULL;
                 *offset = 0;
@@ -275,9 +273,18 @@ static void *segsum_get(struct super_block *sb, struct buffer_head **pbh,
         return ptr;
 }
 
-static void segsum_skip(struct super_block *sb, struct buffer_head **pbh,
-                        unsigned int *offset, unsigned int bytes,
-                        unsigned long count)
+/**
+ * nilfs_skip_summary_info - skip items on summary blocks of a log
+ * @nilfs: nilfs object
+ * @pbh: the current buffer head on summary blocks [in, out]
+ * @offset: the current byte offset on summary blocks [in, out]
+ * @bytes: byte size of the item to be skipped
+ * @count: number of items to be skipped
+ */
+static void nilfs_skip_summary_info(struct the_nilfs *nilfs,
+                                    struct buffer_head **pbh,
+                                    unsigned int *offset, unsigned int bytes,
+                                    unsigned long count)
 {
         unsigned int rest_item_in_current_block
                 = ((*pbh)->b_size - *offset) / bytes;
@@ -294,36 +301,46 @@ static void segsum_skip(struct super_block *sb, struct buffer_head **pbh,
                 *offset = bytes * (count - (bcnt - 1) * nitem_per_block);
 
                 brelse(*pbh);
-                *pbh = sb_bread(sb, blocknr + bcnt);
+                *pbh = __bread(nilfs->ns_bdev, blocknr + bcnt,
+                               nilfs->ns_blocksize);
         }
 }
 
-static int
-collect_blocks_from_segsum(struct nilfs_sb_info *sbi, sector_t sum_blocknr,
-                           struct nilfs_segsum_info *ssi,
-                           struct list_head *head)
+/**
+ * nilfs_scan_dsync_log - get block information of a log written for data sync
+ * @nilfs: nilfs object
+ * @start_blocknr: start block number of the log
+ * @sum: log summary information
+ * @head: list head to add nilfs_recovery_block struct
+ */
+static int nilfs_scan_dsync_log(struct the_nilfs *nilfs, sector_t start_blocknr,
+                                struct nilfs_segment_summary *sum,
+                                struct list_head *head)
 {
         struct buffer_head *bh;
         unsigned int offset;
-        unsigned long nfinfo = ssi->nfinfo;
-        sector_t blocknr = sum_blocknr + ssi->nsumblk;
+        u32 nfinfo, sumbytes;
+        sector_t blocknr;
         ino_t ino;
         int err = -EIO;
 
+        nfinfo = le32_to_cpu(sum->ss_nfinfo);
         if (!nfinfo)
                 return 0;
 
-        bh = sb_bread(sbi->s_super, sum_blocknr);
+        sumbytes = le32_to_cpu(sum->ss_sumbytes);
+        blocknr = start_blocknr + DIV_ROUND_UP(sumbytes, nilfs->ns_blocksize);
+        bh = __bread(nilfs->ns_bdev, start_blocknr, nilfs->ns_blocksize);
         if (unlikely(!bh))
                 goto out;
 
-        offset = le16_to_cpu(
-                ((struct nilfs_segment_summary *)bh->b_data)->ss_bytes);
+        offset = le16_to_cpu(sum->ss_bytes);
         for (;;) {
                 unsigned long nblocks, ndatablk, nnodeblk;
                 struct nilfs_finfo *finfo;
 
-                finfo = segsum_get(sbi->s_super, &bh, &offset, sizeof(*finfo));
+                finfo = nilfs_read_summary_info(nilfs, &bh, &offset,
+                                                sizeof(*finfo));
                 if (unlikely(!finfo))
                         goto out;
 
@@ -336,8 +353,8 @@ collect_blocks_from_segsum(struct nilfs_sb_info *sbi, sector_t sum_blocknr,
                         struct nilfs_recovery_block *rb;
                         struct nilfs_binfo_v *binfo;
 
-                        binfo = segsum_get(sbi->s_super, &bh, &offset,
-                                           sizeof(*binfo));
+                        binfo = nilfs_read_summary_info(nilfs, &bh, &offset,
+                                                        sizeof(*binfo));
                         if (unlikely(!binfo))
                                 goto out;
 
@@ -355,9 +372,9 @@ collect_blocks_from_segsum(struct nilfs_sb_info *sbi, sector_t sum_blocknr,
                 }
                 if (--nfinfo == 0)
                         break;
-                blocknr += nnodeblk; /* always 0 for the data sync segments */
-                segsum_skip(sbi->s_super, &bh, &offset, sizeof(__le64),
-                            nnodeblk);
+                blocknr += nnodeblk; /* always 0 for data sync logs */
+                nilfs_skip_summary_info(nilfs, &bh, &offset, sizeof(__le64),
+                                        nnodeblk);
                 if (unlikely(!bh))
                         goto out;
         }
@@ -467,14 +484,14 @@ static int nilfs_prepare_segment_for_recovery(struct the_nilfs *nilfs,
         return err;
 }
 
-static int nilfs_recovery_copy_block(struct nilfs_sb_info *sbi,
+static int nilfs_recovery_copy_block(struct the_nilfs *nilfs,
                                      struct nilfs_recovery_block *rb,
                                      struct page *page)
 {
         struct buffer_head *bh_org;
         void *kaddr;
 
-        bh_org = sb_bread(sbi->s_super, rb->blocknr);
+        bh_org = __bread(nilfs->ns_bdev, rb->blocknr, nilfs->ns_blocksize);
         if (unlikely(!bh_org))
                 return -EIO;
 
@@ -485,13 +502,14 @@ static int nilfs_recovery_copy_block(struct nilfs_sb_info *sbi,
         return 0;
 }
 
-static int recover_dsync_blocks(struct nilfs_sb_info *sbi,
-                                struct list_head *head,
-                                unsigned long *nr_salvaged_blocks)
+static int nilfs_recover_dsync_blocks(struct the_nilfs *nilfs,
+                                      struct nilfs_sb_info *sbi,
+                                      struct list_head *head,
+                                      unsigned long *nr_salvaged_blocks)
 {
         struct inode *inode;
         struct nilfs_recovery_block *rb, *n;
-        unsigned blocksize = sbi->s_super->s_blocksize;
+        unsigned blocksize = nilfs->ns_blocksize;
         struct page *page;
         loff_t pos;
         int err = 0, err2 = 0;
@@ -505,13 +523,16 @@ static int recover_dsync_blocks(struct nilfs_sb_info *sbi,
                 }
 
                 pos = rb->blkoff << inode->i_blkbits;
-                page = NULL;
-                err = block_write_begin(NULL, inode->i_mapping, pos, blocksize,
-                                        0, &page, NULL, nilfs_get_block);
-                if (unlikely(err))
+                err = block_write_begin(inode->i_mapping, pos, blocksize,
+                                        0, &page, nilfs_get_block);
+                if (unlikely(err)) {
+                        loff_t isize = inode->i_size;
+                        if (pos + blocksize > isize)
+                                vmtruncate(inode, isize);
                         goto failed_inode;
+                }
 
-                err = nilfs_recovery_copy_block(sbi, rb, page);
+                err = nilfs_recovery_copy_block(nilfs, rb, page);
                 if (unlikely(err))
                         goto failed_page;
 
@@ -551,18 +572,20 @@ static int recover_dsync_blocks(struct nilfs_sb_info *sbi,
 /**
  * nilfs_do_roll_forward - salvage logical segments newer than the latest
  * checkpoint
+ * @nilfs: nilfs object
  * @sbi: nilfs_sb_info
- * @nilfs: the_nilfs
  * @ri: pointer to a nilfs_recovery_info
  */
 static int nilfs_do_roll_forward(struct the_nilfs *nilfs,
                                  struct nilfs_sb_info *sbi,
                                  struct nilfs_recovery_info *ri)
 {
-        struct nilfs_segsum_info ssi;
+        struct buffer_head *bh_sum = NULL;
+        struct nilfs_segment_summary *sum;
         sector_t pseg_start;
         sector_t seg_start, seg_end;  /* Starting/ending DBN of full segment */
         unsigned long nsalvaged_blocks = 0;
+        unsigned int flags;
         u64 seg_seq;
         __u64 segnum, nextnum = 0;
         int empty_seg = 0;
@@ -581,8 +604,14 @@ static int nilfs_do_roll_forward(struct the_nilfs *nilfs,
         nilfs_get_segment_range(nilfs, segnum, &seg_start, &seg_end);
 
         while (segnum != ri->ri_segnum || pseg_start <= ri->ri_pseg_start) {
+                brelse(bh_sum);
+                bh_sum = nilfs_read_log_header(nilfs, pseg_start, &sum);
+                if (!bh_sum) {
+                        err = -EIO;
+                        goto failed;
+                }
 
-                ret = load_segment_summary(sbi, pseg_start, seg_seq, &ssi);
+                ret = nilfs_validate_log(nilfs, seg_seq, bh_sum, sum);
                 if (ret) {
                         if (ret == NILFS_SEG_FAIL_IO) {
                                 err = -EIO;
@@ -590,33 +619,38 @@ static int nilfs_do_roll_forward(struct the_nilfs *nilfs,
                         }
                         goto strayed;
                 }
-                if (unlikely(NILFS_SEG_HAS_SR(&ssi)))
+
+                flags = le16_to_cpu(sum->ss_flags);
+                if (flags & NILFS_SS_SR)
                         goto confused;
 
                 /* Found a valid partial segment; do recovery actions */
-                nextnum = nilfs_get_segnum_of_block(nilfs, ssi.next);
+                nextnum = nilfs_get_segnum_of_block(nilfs,
+                                                    le64_to_cpu(sum->ss_next));
                 empty_seg = 0;
-                nilfs->ns_ctime = ssi.ctime;
-                if (!(ssi.flags & NILFS_SS_GC))
-                        nilfs->ns_nongc_ctime = ssi.ctime;
+                nilfs->ns_ctime = le64_to_cpu(sum->ss_create);
+                if (!(flags & NILFS_SS_GC))
+                        nilfs->ns_nongc_ctime = nilfs->ns_ctime;
 
                 switch (state) {
                 case RF_INIT_ST:
-                        if (!NILFS_SEG_LOGBGN(&ssi) || !NILFS_SEG_DSYNC(&ssi))
+                        if (!(flags & NILFS_SS_LOGBGN) ||
+                            !(flags & NILFS_SS_SYNDT))
                                 goto try_next_pseg;
                         state = RF_DSYNC_ST;
                         /* Fall through */
                 case RF_DSYNC_ST:
-                        if (!NILFS_SEG_DSYNC(&ssi))
+                        if (!(flags & NILFS_SS_SYNDT))
                                 goto confused;
 
-                        err = collect_blocks_from_segsum(
-                                sbi, pseg_start, &ssi, &dsync_blocks);
+                        err = nilfs_scan_dsync_log(nilfs, pseg_start, sum,
+                                                   &dsync_blocks);
                         if (unlikely(err))
                                 goto failed;
-                        if (NILFS_SEG_LOGEND(&ssi)) {
-                                err = recover_dsync_blocks(
-                                        sbi, &dsync_blocks, &nsalvaged_blocks);
+                        if (flags & NILFS_SS_LOGEND) {
+                                err = nilfs_recover_dsync_blocks(
+                                        nilfs, sbi, &dsync_blocks,
+                                        &nsalvaged_blocks);
                                 if (unlikely(err))
                                         goto failed;
                                 state = RF_INIT_ST;
@@ -627,7 +661,7 @@ static int nilfs_do_roll_forward(struct the_nilfs *nilfs,
  try_next_pseg:
                 if (pseg_start == ri->ri_lsegs_end)
                         break;
-                pseg_start += ssi.nblocks;
+                pseg_start += le32_to_cpu(sum->ss_nblocks);
                 if (pseg_start < seg_end)
                         continue;
                 goto feed_segment;
@@ -652,8 +686,9 @@ static int nilfs_do_roll_forward(struct the_nilfs *nilfs,
                 ri->ri_need_recovery = NILFS_RECOVERY_ROLLFORWARD_DONE;
         }
  out:
+        brelse(bh_sum);
         dispose_recovery_list(&dsync_blocks);
-        nilfs_detach_writer(sbi->s_nilfs, sbi);
+        nilfs_detach_writer(nilfs, sbi);
         return err;
 
  confused:
@@ -667,7 +702,6 @@ static int nilfs_do_roll_forward(struct the_nilfs *nilfs,
 }
 
 static void nilfs_finish_roll_forward(struct the_nilfs *nilfs,
-                                      struct nilfs_sb_info *sbi,
                                       struct nilfs_recovery_info *ri)
 {
         struct buffer_head *bh;
@@ -677,7 +711,7 @@ static void nilfs_finish_roll_forward(struct the_nilfs *nilfs,
             nilfs_get_segnum_of_block(nilfs, ri->ri_super_root))
                 return;
 
-        bh = sb_getblk(sbi->s_super, ri->ri_lsegs_start);
+        bh = __getblk(nilfs->ns_bdev, ri->ri_lsegs_start, nilfs->ns_blocksize);
         BUG_ON(!bh);
         memset(bh->b_data, 0, bh->b_size);
         set_buffer_dirty(bh);
@@ -690,9 +724,8 @@ static void nilfs_finish_roll_forward(struct the_nilfs *nilfs,
 }
 
 /**
- * nilfs_recover_logical_segments - salvage logical segments written after
- * the latest super root
- * @nilfs: the_nilfs
+ * nilfs_salvage_orphan_logs - salvage logs written after the latest checkpoint
+ * @nilfs: nilfs object
  * @sbi: nilfs_sb_info
  * @ri: pointer to a nilfs_recovery_info struct to store search results.
  *
@@ -709,9 +742,9 @@ static void nilfs_finish_roll_forward(struct the_nilfs *nilfs,
  *
  * %-ENOMEM - Insufficient memory available.
  */
-int nilfs_recover_logical_segments(struct the_nilfs *nilfs,
-                                   struct nilfs_sb_info *sbi,
-                                   struct nilfs_recovery_info *ri)
+int nilfs_salvage_orphan_logs(struct the_nilfs *nilfs,
+                              struct nilfs_sb_info *sbi,
+                              struct nilfs_recovery_info *ri)
 {
         int err;
 
@@ -751,7 +784,7 @@ int nilfs_recover_logical_segments(struct the_nilfs *nilfs,
                         goto failed;
                 }
 
-                nilfs_finish_roll_forward(nilfs, sbi, ri);
+                nilfs_finish_roll_forward(nilfs, ri);
         }
 
  failed:
@@ -762,7 +795,6 @@ int nilfs_recover_logical_segments(struct the_nilfs *nilfs,
 /**
  * nilfs_search_super_root - search the latest valid super root
  * @nilfs: the_nilfs
- * @sbi: nilfs_sb_info
  * @ri: pointer to a nilfs_recovery_info struct to store search results.
  *
  * nilfs_search_super_root() looks for the latest super-root from a partial
@@ -775,14 +807,19 @@ int nilfs_recover_logical_segments(struct the_nilfs *nilfs,
  * %-EINVAL - No valid segment found
  *
  * %-EIO - I/O error
+ *
+ * %-ENOMEM - Insufficient memory available.
  */
-int nilfs_search_super_root(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi,
+int nilfs_search_super_root(struct the_nilfs *nilfs,
                             struct nilfs_recovery_info *ri)
 {
-        struct nilfs_segsum_info ssi;
+        struct buffer_head *bh_sum = NULL;
+        struct nilfs_segment_summary *sum;
         sector_t pseg_start, pseg_end, sr_pseg_start = 0;
         sector_t seg_start, seg_end; /* range of full segment (block number) */
         sector_t b, end;
+        unsigned long nblocks;
+        unsigned int flags;
         u64 seg_seq;
         __u64 segnum, nextnum = 0;
         __u64 cno;
@@ -801,17 +838,24 @@ int nilfs_search_super_root(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi,
         /* Read ahead segment */
         b = seg_start;
         while (b <= seg_end)
-                sb_breadahead(sbi->s_super, b++);
+                __breadahead(nilfs->ns_bdev, b++, nilfs->ns_blocksize);
 
         for (;;) {
-                /* Load segment summary */
-                ret = load_segment_summary(sbi, pseg_start, seg_seq, &ssi);
+                brelse(bh_sum);
+                ret = NILFS_SEG_FAIL_IO;
+                bh_sum = nilfs_read_log_header(nilfs, pseg_start, &sum);
+                if (!bh_sum)
+                        goto failed;
+
+                ret = nilfs_validate_log(nilfs, seg_seq, bh_sum, sum);
                 if (ret) {
                         if (ret == NILFS_SEG_FAIL_IO)
                                 goto failed;
                         goto strayed;
                 }
-                pseg_end = pseg_start + ssi.nblocks - 1;
+
+                nblocks = le32_to_cpu(sum->ss_nblocks);
+                pseg_end = pseg_start + nblocks - 1;
                 if (unlikely(pseg_end > seg_end)) {
                         ret = NILFS_SEG_FAIL_CONSISTENCY;
                         goto strayed;
@@ -821,11 +865,13 @@ int nilfs_search_super_root(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi,
                 ri->ri_pseg_start = pseg_start;
                 ri->ri_seq = seg_seq;
                 ri->ri_segnum = segnum;
-                nextnum = nilfs_get_segnum_of_block(nilfs, ssi.next);
+                nextnum = nilfs_get_segnum_of_block(nilfs,
+                                                    le64_to_cpu(sum->ss_next));
                 ri->ri_nextnum = nextnum;
                 empty_seg = 0;
 
-                if (!NILFS_SEG_HAS_SR(&ssi) && !scan_newer) {
+                flags = le16_to_cpu(sum->ss_flags);
+                if (!(flags & NILFS_SS_SR) && !scan_newer) {
                         /* This will never happen because a superblock
                            (last_segment) always points to a pseg
                            having a super root. */
@@ -836,14 +882,15 @@ int nilfs_search_super_root(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi,
                 if (pseg_start == seg_start) {
                         nilfs_get_segment_range(nilfs, nextnum, &b, &end);
                         while (b <= end)
-                                sb_breadahead(sbi->s_super, b++);
+                                __breadahead(nilfs->ns_bdev, b++,
+                                             nilfs->ns_blocksize);
                 }
-                if (!NILFS_SEG_HAS_SR(&ssi)) {
-                        if (!ri->ri_lsegs_start && NILFS_SEG_LOGBGN(&ssi)) {
+                if (!(flags & NILFS_SS_SR)) {
+                        if (!ri->ri_lsegs_start && (flags & NILFS_SS_LOGBGN)) {
                                 ri->ri_lsegs_start = pseg_start;
                                 ri->ri_lsegs_start_seq = seg_seq;
                         }
-                        if (NILFS_SEG_LOGEND(&ssi))
+                        if (flags & NILFS_SS_LOGEND)
                                 ri->ri_lsegs_end = pseg_start;
                         goto try_next_pseg;
                 }
@@ -854,12 +901,12 @@ int nilfs_search_super_root(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi,
                 ri->ri_lsegs_start = ri->ri_lsegs_end = 0;
 
                 nilfs_dispose_segment_list(&segments);
-                nilfs->ns_pseg_offset = (sr_pseg_start = pseg_start)
-                        + ssi.nblocks - seg_start;
+                sr_pseg_start = pseg_start;
+                nilfs->ns_pseg_offset = pseg_start + nblocks - seg_start;
                 nilfs->ns_seg_seq = seg_seq;
                 nilfs->ns_segnum = segnum;
                 nilfs->ns_cno = cno;  /* nilfs->ns_cno = ri->ri_cno + 1 */
-                nilfs->ns_ctime = ssi.ctime;
+                nilfs->ns_ctime = le64_to_cpu(sum->ss_create);
                 nilfs->ns_nextnum = nextnum;
 
                 if (scan_newer)
@@ -870,15 +917,9 @@ int nilfs_search_super_root(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi,
                         scan_newer = 1;
                 }
 
-                /* reset region for roll-forward */
-                pseg_start += ssi.nblocks;
-                if (pseg_start < seg_end)
-                        continue;
-                goto feed_segment;
-
  try_next_pseg:
                 /* Standing on a course, or met an inconsistent state */
-                pseg_start += ssi.nblocks;
+                pseg_start += nblocks;
                 if (pseg_start < seg_end)
                         continue;
                 goto feed_segment;
@@ -909,6 +950,7 @@ int nilfs_search_super_root(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi,
 
  super_root_found:
         /* Updating pointers relating to the latest checkpoint */
+        brelse(bh_sum);
         list_splice_tail(&segments, &ri->ri_used_segments);
         nilfs->ns_last_pseg = sr_pseg_start;
         nilfs->ns_last_seq = nilfs->ns_seg_seq;
@@ -916,6 +958,7 @@ int nilfs_search_super_root(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi,
         return 0;
 
  failed:
+        brelse(bh_sum);
         nilfs_dispose_segment_list(&segments);
         return (ret < 0) ? ret : nilfs_warn_segment_error(ret);
 }